1. Field of the Invention
The invention relates to a textile machine, such as a card machine and more specifically to revolving flat arrangements of a revolving flat card. The flat rod of a revolving flat card comprises, in any case, a clothing receiving part which must be connected to a drive apparatus. The flat rod may comprise end heads or caps which can be connected both with the clothing receiving part as well as with the drive apparatus.
2. Discussion of the Background of the Invention and Material Information
The invention provides, in a first aspect, a connecting system between a revolving flat rod of a revolving flat card and a flexible drive belt for the flat rods. Such a connecting system is known, for example, from prior art German Patent Publication DE-A-3907 396 and cognate U.S. Pat. No. 4,955,111. It is described and shown therein, particularly in FIG. 4 that the end of the flat head is provided with a continuous bore of the shape of a hollow cylinder and the drive belt is provided with noses or projections which engage in respective bores in the flat heads. In a further embodiment, the flat head is provided with teeth having gaps between the teeth, into which gaps the teeth of a double toothed belt engage. It is important for the flat rods which are situated between the flexible bow and the toothed belt that they are sufficiently guided thereby. In the zone of the deflection or reorientation, however, a deflection of the flexible bow is required, so that the flat rods do not fall down or disengage from the toothed belt. After the deflection or reorientation the flat rods are easily removable from the toothed belt as they lie or reside freely thereon.
The above-noted apparatus has the disadvantage that the flat rods have to be guided mechanically (by means specially provided for this purpose) during the deflection or reorientation and, partly, on the rising and falling path of the endless loop of movements of the revolving flat. This requires substantially increased expenditures.
Prior art German Patent Publication DE-A-3814 412 and cognate U.S. Pat. No. 4,987,647, in FIG. 8, disclose a connecting system for usage with a flat chain, wherein the end part of a fixing bolt is provided with a continuous slot, thus providing two webs or bridges. Every bridge is provided with an outwardly directed nose or projection. The bridges are elastic, so that the noses can snap into a slot in the flat head. The system requires a fixing element(the bolt) which has to be connected to the flat chain itself. This arrangement however does not provide any practical advantages over conventional systems (with a screw instead of a bolt) and has not been implemented commercially.
The invention provides, in a second aspect thereof, a flat rod which is formed as a hollow profile and is provided with separately formed end heads. Such a flat rod is described, for example, in prior art U.S. Pat. No. 4,827,573 and consists of a steel tube drawn through a profile mold. At either end of the flat rod massive head pieces are provided for attachment to a drive belt. Such head pieces are connected to the flat rod either by welding or with rivets or screws, so that they can be exchanged when they have become unusable owing to wear and tear.
It has been determined that the welded connection occasionally leads to tension or stress in the flat rod and that then it is necessary to exchange the whole flat rod. The same also applies for screw and rivet connections, i.e., the applied connecting force (rotation of the screw or pressure during riveting) within a certain tolerance range for all flat rods so as to prevent excessive tension or stress.